The present invention relates in general to thermally processing film and more particularly concerns novel apparatus and techniques for thermally processing sheet film automatically and uniformly. This device will process sheet film of any size up to and including roll film. The invention achieves these advantages with a relatively compact inexpensive machine that operates with relatively high reliability.
Very high resolution film, such as that used in air reconnaissance and microfilm applications, is often of a type that develops in response to heat in a dry process. To effect uniform development necessary for providing a high resolution image, it has usually been found important to uniformly heat the entire film surface during the development process with the degree of development related to the product of the temperature to which the film is subjected and the time the temperature is applied to the film. Reasonably satisfactory performance has been obtained for developing long rolls of film; however, difficulties have been encountered in providing methods and means for continuously developing film sheets. Problems include maintaining uniform temperature over the developing heat source, maintaining the film to be developed in contact with the heat source or otherwise establishing a relationship between the heat source and the film sheet so that the film sheet receives uniform development.
Accordingly, it is an important object of this invention to provide methods and means for thermally developing film which overcomes one or more of the problems discussed above.
It is another object of the invention to achieve the preceding object with a continuous process for developing film sheets.
It is another object of the invention to achieve one or more of the preceding objects while uniformly developing each
It is still a further object of the invention to achieve one or more of the preceding objects with compact apparatus that is relatively inexpensive, reliable, relatively easy to operate by unskilled personnel and uniformly develops film to produce high resolution images with negligible development deterioration in the image quality.